Automatic tbactob and plow hitch



. 1'640 237 Aug. 23, 1927. I P M. HEFFERNAN 9 I I AUTOMATIC TRACTOR AND PLOW HITCH Filed April 12, 1926 warw Patented Aug. 23, 1927.

llNlTED STATES rarest ent ce.

PATRICK lVEIGltTAEL HEFJFERNAN, OF MOONLIGHT, PALMERSTON $011111, NEW

. ZEALAND.

AUTOMA'QXC TRACTOR AND PLOW HITCH.

Application filed Apri1 12, 1926, Serial No. 191,425, and in New Zealand. September 24:, 1925.

This invention relates to improvements in an automatic tractor and plow hitch, which will release the plow from the tractor when an increased resistance to traction is encountered, second, on the removal of the obstruction, and operation of the tractor in the reverse direction, will be automatically hitched with the plow.

I attain these objects by the mechanism illustrated in the accompanying drawing, in which Figure 1 is a plan of the device embodying the present invention.

Figure 2 is a side elevation of the device.

Figure 3 is a side elevation of the connecting shackle.

Figured is a plan View of the connecting shackle.

Similar numerals refer to similar parts throughout the several views.

Referring to Figures 1 and 2 which shows a plan and side elevation of the hitching device, two bifurcated members 1 are disposed one above the other in alignment, and spaced apart in order that the drawbar of the plow 14 may be inserted between the terminals 1 thereof and be secured thereto by the bolts 15. I p p A member 2, til-shaped in cross-sectiomlias an inner guide plate 9 secured between its upper and lower plates by the pins 9, and is adapted. to be slidably moved on the forks 1 ot' the bifurcated members 1..

A rod 12 termed with an eye 12 atone end is disposed between the sides of the U shaped member 2 w ich extend beyond the guide plate 9, and is pivoted on the pin 10 which extends through the upper and lower plates of the U shaped member 2.

The rod 12 lies between the plates 1 and extends beyond the edges 1 of the latter, and a helical spring 11, surrounding the extended part of the rod 12 has is inner end abutting; against the edges 1 of the plates 1, the required compression being given the helical s i'ing 11 by a washer and threaded nut 13 on the threaded end of the rod- 12.

A rotatable catch 18 having a plurality of arms is disposed between the forks l of the bifurcated members 1, and is secured on the spindle 21 which is rotatably mounted in orifices in the forks 1*.

The spindle 21 extends beyond the outer surface of the upper "fork 1 A spiral spring 22 surrounds the spindle 21 and has its lower terminal secured to thetork 1 and its upper terminal secured to the nut or plate16 loosely mounted on the spindle 21.

The ratchet wheel 17 is secured on the spindle 21, above the nut or plate 16 which has a pawl 19 pivoted. thereon on a pin 19. The pawl 19 is held in engagement with the ratchet wheel 17 by the wave spring 20.

The ends of the spindle 21 are th eaded and carry nuts 21. which bear, respectively, against the lower side of one fork 1* and the ratchet wheel 17.

The ends of the arms 18 of the tour arm catch 18 are adapted to engage with a roller 1 disposed between the two plates of the shaped member 2, and is rotatable on the pin 3 which extends through the upper and lower plates of the slidable U shaped mem her 2.

The forked end or the shackle 5 is secured to the drawbar 8 of a tractor by the pin 7. The catch 18 is adapted to have one of its arms 18 pass inside the shackle 5, with one of its edges contacting with the cross mem ber of the shackle 5. b

To hold the shackle 5 in the operative position a stay 6 has its opposite ends secured to the shackle 5 and to the drawbar 8 of the tractor by the pins 6".

Referring to- Figures 3 and l of the drawing, a shackle 5 is shown having two pro f ing horns 5 to act as a guide and cause the shackle 5, when the "rector is reversed, to engage with one of the or tour a med catch 18.

The mode ot operation as follows: The device secured to the plow drawbar 1- the nut 1.6 is rotated to wind the spring;

l he shackle on the drawbar of the tractor is hitched to one of the arms of the tour armed catch 18, with theouter end 18' of s lci arm bearing against the roller (l in the slidable t3 ped. member creased resi ance to the forward movement of the plow encountered, the pressure of said arm 01' the rotatable. catch 18, against the roller 1 mov s the slidable ll shaped member 2 against the resistance of the compression spring 11, permitting the end 8 of said arm to pass by the roller 1, thus releasing the shackle 5 from engagement with the arm of the rotatablev catch 18. When this occurs the energy stored in the compression spring 11 restores the slidable When an inarms 01' the two U shaped member 2 into the operative position, and the energy in the coiled spring 22 rotates the two or four armed catch 18 thus bringing the following arm of the rotatable catch which is in engagement with the roller 1. As the tractor moves backward, the shackle 5 will rotate said arm of the rotatable catch 18 in a backward direction against the resistance of the coiled spring 22 until the shackle 5 is moved sufficiently backward in the space between the forks of the bifurcated members .0 permit the cross member of the shackle to ride over the end of said arm of the rotatable catch 18. The rotatable catch 18 will then immediately be caused by the spring 22' to rotate in the opposite direction, the arm of the catch passing between the forks of the shackle 5 into engagement with the roller 4;, in the operative position for haulage by the tractor.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is 1. A tractor and plow hitch, comprising two bifurcated members disposed one above the other in alignment and spaced to permit a plow drawbar to be inserted between and secured thereto, and. means for releasably connecting a tractor drawbar to said hitch comprising a member sl'idably mounted on a pair of aligned arms of said bifurcated members and a multi-arm clutch rotatably mounted between the other pair of aligned arms of said bifurcated members and having its arms successively engageable with said slidable member.

2. A tractor and plow hitch, comprising two bifurcated members disposed one above the other in alignment, a member slidable on the one pair of forks, a rod disposed between and extending beyond the forks on which the slidable member is disposed and pivotally connected to the rear end of the said slidable member, means adjustably mounted on said rod adjacent its opposite end, a helical spring on said rod with one of its ends abutting against the edges of the one pair of forks and its other end bearing against said adjustable means, a catch member mounted to rotate between the other pair of forks, said catch member having a plurality of arms adapted to successively engage said slidable member between its rear and forward ends, and spring means tending to rotate said atch member toward the forward end of said slidable member.

A tractor and plow hitch, comprising two bifurcated members disposed one above the other in alignment, a member slidable 011 one of said bifurcated members, a spindle rotatable in the other pair of forks opposite to that on which the slidable member is mounted, a four-arm catch secured to the said spindle between the said forks, a coiled spring on one end of the said spindle and having its lower terminal secured to the one plate of the fork, a plate loosely mounted on the spindle and to which the upper end of the coiled spring is attached, a pawl pivoted on the said plate, a ratchet wheel secured to said spindle and engaged by said pawl, and a spring to hold the pawl in the operative position.

l. A tractor and plow hitch comprising two bifurcated members disposed one above the other in alignment, a me nber slidable on one of said bifurcated members, a spindle rotatable in the pair of forks opposite to that on which the slidable member is mounted, a four-arm catch secured to the said spindle between the said forks, and a roller mounted on the slidable member with which the ends ofthe arms of said catch are adapted to successively engage.

In testimony whereof, I affix my signature.

PATRICK M. HEFFERNAN. 

